HMS Beagle wrote:
Regarding air pressure: there are charts from the manufacturers suggesting pressures for loads. However there are really two questions: what is best for tire longevity, and what is best for handling feel. The answers to those questions may not match. According to the charts I should be fine with 55 lbs in the rears, but the handling is much better at 75. So I run 75 with the camper in.
I have always used these charts for loaded and unloaded. My goal is to have the tires wear flat across all the tread and have had pretty good luck using this.
I adopted this method in 1998. My ram 2500 said something like Rear = 45psi empty, 80psi loaded. within 5000 miles the center of the good years was showing signs of over inflation (center wearing out).
I called Dodge who told me "when we say empty, we mean full of tools but not carrying any load". :(.
I switched to inflation charts (what could I loose, I was wearing center of tires out empty).
I seem to recall running around 28-30psi empty and they wore perfect.
I hear another method is to mark the tire with chalk across the thread and run a couple feet down a straight road to see if the chalk comes off all the tire.
My current dually I am running rear pressure 40-45psi empty (only because I been to chicken to go lower), 55psi with 5th wheel and 65psi with Pickup camper and hitch of box trailer hooked up.
My new truck also has the pressure indicator in dash.
I understand an under inflated tire generates more heat than an over inflated tire. as tires get hot, the pressure climbs.
based on door sticker, my front tires are inflated to 80 psi.
I can see the front tires gain around 5-7 PSI in a couple miles of driving as the tire temps come up.
If I am running 65psi empty in the rear the rear tire pressure might go up 1psi in that same distance. IF I run rear PSI based on weight charts the PSI climbs the same speed as the front tires as they heat up :).
For what its worth?
